Recently, along with the widespread use of various image processing apparatuses for digital image processing, there is an increasing demand for a high-performance image compression and decompression apparatus for required image processing. For example, Jpn. Pat. Appln. KOKAI Publication No. 7-307869 discloses a conventional image compression and decompression apparatus. This apparatus smoothes data according to an identification signal before compression and stores compressed data and the identification signal. After decompressing the compressed data, the apparatus performs highlight processing according to the identification signal for improving the image quality. This apparatus provides appropriate highlighting by performing processes according to identification signals corresponding to image types, allowing high-quality image processing after compression and decompression.
However, the image processing such as highlighting does not correspond to compression and decompression, causing a possible problem of accordingly degrading the image quality.